To change the domain name on Squarespace, you can follow these steps.
#1. Click Settings icon
#2. Click Domains & Email > Click Domains
#3. You can change the primary domain or Squarespace built-in domain. Here we will try changing the built-in domain
#4. Enter a new domain name and Save.
Note: If you want to change it to designagency.squarespace.com, just enter “designagency” to the box, like this
#5. If you change the Primary Domain, you will need to Disconnect Currently primary domain
#6. Then choose one of two options and connect to your new domain
You can follow this guide if you need to connect the Godaddy domain to your Squarespace site.